Risk of Developing Rheumatoid Arthritis in Adults with Asthma: A Population-Based Case-Control Study
Saturday, March 5, 2016
South Exhibit Hall H (Convention Center)
Mary C Rolfes, Youn Ho Shin, MD, Chung I. Wi, MD, Cynthia S Crowson, MS, Richard S Pendegraft, Euijung Ryu, PhD, Young J. Juhn, MD MPH
Rationale: The relationship between asthma and the risk of systemic inflammatory disease such as rheumatoid arthritis (RA) is poorly understood.  We determined whether asthma status is associated with the risk of incident RA among adults.

Methods: We conducted a retrospective population-based case-control study, which enrolled a population-based incident RA cohort (2004-2007) and their 1:1 birth year- and gender-matched controls residing in Olmsted County, MN.  We performed comprehensive medical record reviews to ascertain asthma status of cases and controls using predetermined criteria for asthma.  The frequency of a history of asthma prior to index date was compared between cases and their matched controls. Data were fit to logistic regression models to calculate odds ratios and the corresponding 95% confidence interval (CI).

Results: We enrolled 136 RA cases and 134 controls in the study, of whom 84 (31.1%) were male and 256 (94.8%) were Caucasians. The median ages at the index date were 52.4 years for the RA cases and 53.0 years for controls. Of the 136 RA cases, 38 (28%) had a history of asthma, whereas 21 of 134 controls (16%) had a history of asthma (adjusted odds ratio [aOR], 2.16; 95% confidence interval [CI], 1.18-3.97, p=0.013) after adjusting for age and sex. The similar trends were observed when a physician diagnosis of asthma was used for ascertaining asthma status (aOR, 2.39; 95% CI, 1.27-4.50, p=0.007).

Conclusions: Patients with asthma as a T-helper 2 condition had a significantly higher risk of RA as a T-helper 1 proinflammatory condition than healthy individuals.